Determination of Bacterial Species and their Antibiotic Susceptibility Profiles Isolated from Patients with Urinary Tract Infection in a Private Hospital in Istanbul

Abstract

Aim: One of the most common bacterial infections in humans in the community and hospital settings is urinary tract infections. It is seen in the second frequency, with a rate of 25% among all infectious diseases. Urinary tract infections are caused by microorganisms that cause an inflammatory response in the urinary tract epithelium, more than 95% of which are bacterial agents. The aim of this study is to retrospectively examine and evaluate the bacteria isolated and their resistance/sensitivity to antibiotics as a result of microbiological analyzes of urine samples taken from patients who came to different services and polyclinics and inpatients with signs of urinary tract infection of a private hospital in Istanbul between 2017-2021 with the complaint of urinary tract infection.Method: In the study, 772 urine samples sent to the microbiology laboratory of the hospital between 2017-2021 were analyzed retrospectively in terms of isolated bacteria and their resistance/sensitivity to antibiotics. Data analysis was performed with SPSS Statistics version 26. Categorical variables were calculated as numbers and percentages. The difference between categorical variables was analyzed using the chi-square test.Results: In the study, microbiological culture/antibiogram results of urine samples of 772 patients, 572 of whom were female (74%) and 200 were male (26%), were examined. When the age distributions of the patients are examined; 6% are 0-15 years old, 5.9% are 15-24 years old, 33.9% are 25-49 years old and 54.2% are 49 years old and over. A total of 32 different bacterial species were isolated from urine samples, and the most isolated bacterial species were respectively; Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. Among the antibiotics to which Escherichia coli isolates are most sensitive; amikacin (97.2%), meropenem (95.3%), imipenem (95.1%), colistin (94.7%), ertapenem (92%), tazobactam-piperacillin (88.6%), nitrofurantoin (87.7%), gentamicin (84.3%), ticarcillin-clavulanate (83.1%), and cefoxitin (82.9%). The antibiotics with the highest resistance development are respectively; ampicillin (71.3%), ampicillin-sulbactam (69.9%) and amoxicillin-clavulonic acid (49.4%). The antibiotics with the highest sensitivity in Klebsiella pneumoniae isolates are, respectively; colistin (70.4%) and amikacin (69.8%) were most resistant to ampicillin (94.9%), ampicillin - sulbactam (93.5%) and cefazolin (69.6%). In isolated Proteus mirabilis, the highest sensitivity was found to tazobactam-piperacillin (78.8%), aztreonam (78.6%) and meropenem (75%), while the antibiotics with the highest resistance development were nitrofurantoin (72.7%) and colistin (81.5%).Conclusion: Widespread use of antibiotics against UTI pathogens has led to the emergence of antibiotic-resistant strains. The most important reason for the formation of antibacterial resistance is the use of antibiotics for a long time and in insufficient doses. In addition, the wrong choice of antibiotics leads to the development of resistance. This situation affects the treatment process and reveals the need to determine the right chemotherapeutic options for an effective treatment. The antimicrobial resistance distributions of bacteria causing urinary tract infections show differences according to time and region. Because the antibiogram test results take time, patients who apply to clinics and hospitals with the complaint of UTI are usually treated with empirical antibiotics. In the selection of empirical preparations, first of all, the most frequently isolated agent and the antimicrobial agent with the lowest resistance rate should be taken into consideration, and if possible, urine samples should be delivered to the laboratory for agent isolation and antibiogram evaluation before starting antibiotic therapy.